Experimental and 3D CFD investigation on energy separation inside a convergent vortex tube air separator

The vortex tube air separator is an invaluable tool which has the ability to separate a high-pressure fluid into the cold and hot fluid streams. The hot tube is the main part of the vortex tube, along which the energy separation procedure happens. This research has been done to analyze the effect of the convergent angle and cold orifice diameter on thermal efficiency of a convergent vortex tube. The convergent hot tube angle varies over the range of 1 to 9 deg. Attention to the main angle effect denotes that the highest thermal ability could be achieved at beta = 5 deg. Experiments denote that both cooling capability and heating effectiveness reach the highest magnitudes when D-Cold is around 9 mm. After these two stages, the optimized convergent vortex tube is capable of decreasing and rising air temperatures at the cold and the hot sides up to 9.05 K (42.89%) and 10.48 K (44.74%), respectively. A computational fluid dynamics model is employed to predict the performance of the convergent vortex tube. The numerical investigation is done by full 3D steady-state CFD-simulation using FLUENT6.3.26. The results show that the agreement between computation predictions and laboratory measurements is fairly good. (C) 2016 Sharif University of Technology. All rights reserved.